[project @ 2001-06-15 15:20:20 by simonpj]
[ghc-hetmet.git] / ghc / compiler / main / CmdLineOpts.lhs
index ba967f2..181863f 100644 (file)
-%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1995
+
+% (c) The University of Glasgow, 1996-2000
 %
 \section[CmdLineOpts]{Things to do with command-line options}
 
 \begin{code}
-#include "HsVersions.h"
 
 module CmdLineOpts (
-       CmdLineInfo(..), SwitchResult(..),
-       GlobalSwitch(..), SimplifierSwitch(..),
        CoreToDo(..),
+       SimplifierSwitch(..), isAmongSimpl,
        StgToDo(..),
-#ifdef DPH
-       PodizeToDo(..),
-#endif {- Data Parallel Haskell -}
-       
-       classifyOpts,
-       switchIsOn, stringSwitchSet, intSwitchSet,
-       
-       -- to make the interface self-sufficient
-       Maybe, MainIO(..)
+       SwitchResult(..),
+
+       HscLang(..),
+       DynFlag(..),    -- needed non-abstractly by DriverFlags
+       DynFlags(..),
+
+       v_Static_hsc_opts,
+
+       intSwitchSet,
+       switchIsOn,
+       isStaticHscFlag,
+
+       -- Manipulating DynFlags
+       defaultDynFlags,                -- DynFlags
+       dopt,                           -- DynFlag -> DynFlags -> Bool
+       dopt_set, dopt_unset,           -- DynFlags -> DynFlag -> DynFlags
+       dopt_CoreToDo,                  -- DynFlags -> [CoreToDo]
+       dopt_StgToDo,                   -- DynFlags -> [StgToDo]
+       dopt_HscLang,                   -- DynFlags -> HscLang
+       dopt_OutName,                   -- DynFlags -> String
+
+       -- Manipulating the DynFlags state
+       getDynFlags,                    -- IO DynFlags
+       setDynFlags,                    -- DynFlags -> IO ()
+       updDynFlags,                    -- (DynFlags -> DynFlags) -> IO ()
+       dynFlag,                        -- (DynFlags -> a) -> IO a
+       setDynFlag, unSetDynFlag,       -- DynFlag -> IO ()
+       saveDynFlags,                   -- IO ()
+       restoreDynFlags,                -- IO DynFlags
+
+       -- sets of warning opts
+       standardWarnings,
+       minusWOpts,
+       minusWallOpts,
+
+       -- Output style options
+       opt_PprStyle_NoPrags,
+       opt_PprStyle_RawTypes,
+       opt_PprUserLength,
+       opt_PprStyle_Debug,
+
+       -- profiling opts
+       opt_AutoSccsOnAllToplevs,
+       opt_AutoSccsOnExportedToplevs,
+       opt_AutoSccsOnIndividualCafs,
+       opt_AutoSccsOnDicts,
+       opt_SccProfilingOn,
+       opt_DoTickyProfiling,
+
+       -- language opts
+       opt_AllStrict,
+       opt_DictsStrict,
+        opt_MaxContextReductionDepth,
+       opt_IrrefutableTuples,
+       opt_NumbersStrict,
+       opt_Parallel,
+       opt_SMP,
+       opt_NoMonomorphismRestriction,
+       opt_RuntimeTypes,
+
+       -- optimisation opts
+       opt_NoMethodSharing,
+       opt_DoSemiTagging,
+       opt_FoldrBuildOn,
+       opt_LiberateCaseThreshold,
+       opt_StgDoLetNoEscapes,
+       opt_UnfoldCasms,
+        opt_UsageSPOn,
+       opt_UnboxStrictFields,
+       opt_SimplNoPreInlining,
+       opt_SimplDoEtaReduction,
+       opt_SimplDoLambdaEtaExpansion,
+       opt_SimplCaseMerge,
+       opt_SimplExcessPrecision,
+
+       -- Unfolding control
+       opt_UF_CreationThreshold,
+       opt_UF_UseThreshold,
+       opt_UF_FunAppDiscount,
+       opt_UF_KeenessFactor,
+       opt_UF_UpdateInPlace,
+       opt_UF_CheapOp,
+       opt_UF_DearOp,
+
+       -- misc opts
+       opt_InPackage,
+       opt_EmitCExternDecls,
+       opt_EnsureSplittableC,
+       opt_GranMacros,
+       opt_HiVersion,
+       opt_HistorySize,
+       opt_IgnoreAsserts,
+       opt_IgnoreIfacePragmas,
+        opt_NoHiCheck,
+       opt_OmitBlackHoling,
+       opt_OmitInterfacePragmas,
+       opt_NoPruneTyDecls,
+       opt_NoPruneDecls,
+       opt_Static,
+       opt_Unregisterised,
+       opt_EmitExternalCore
     ) where
 
-import MainMonad
-import Maybes          ( maybeToBool, Maybe(..) )
-import Outputable
+#include "HsVersions.h"
+
+import Array   ( array, (//) )
+import GlaExts
+import IOExts  ( IORef, readIORef, writeIORef )
+import Constants       -- Default values for some flags
 import Util
-#ifdef __GLASGOW_HASKELL__
-import PreludeGlaST    -- bad bad bad boy, Will
+import FastTypes
+import Config
+
+import Maybes          ( firstJust )
+import Panic           ( panic )
+
+#if __GLASGOW_HASKELL__ < 301
+import ArrBase ( Array(..) )
+#else
+import PrelArr  ( Array(..) )
 #endif
 \end{code}
 
-A command-line {\em switch} is (generally) either on or off; e.g., the
-``verbose'' (-v) switch is either on or off.  (The \tr{-G<group>}
-switch is an exception; it's set to a string, or nothing.)
+%************************************************************************
+%*                                                                     *
+\subsection{Command-line options}
+%*                                                                     *
+%************************************************************************
+
+The hsc command-line options are split into two categories:
+
+  - static flags
+  - dynamic flags
+
+Static flags are represented by top-level values of type Bool or Int,
+for example.  They therefore have the same value throughout the
+invocation of hsc.
+
+Dynamic flags are represented by an abstract type, DynFlags, which is
+passed into hsc by the compilation manager for every compilation.
+Dynamic flags are those that change on a per-compilation basis,
+perhaps because they may be present in the OPTIONS pragma at the top
+of a module.
+
+Other flag-related blurb:
 
 A list of {\em ToDo}s is things to be done in a particular part of
 processing.  A (fictitious) example for the Core-to-Core simplifier
@@ -45,31 +165,17 @@ main loop (\tr{main/Main.lhs}), in the Core-to-Core processing loop
 (\tr{simplCore/SimplCore.lhs), and in the STG-to-STG processing loop
 (\tr{simplStg/SimplStg.lhs}).
 
-We use function @classifyOpts@ to take raw command-line arguments from
-@GetArgs@ and get back the @CmdLineInfo@, which is what we really
-want.
-
 %************************************************************************
 %*                                                                     *
-\subsection[CmdLineOpts-datatype]{Datatypes associated with command-line options}
+\subsection{Datatypes associated with command-line options}
 %*                                                                     *
 %************************************************************************
 
 \begin{code}
-type CmdLineInfo 
-  = (GlobalSwitch -> SwitchResult,     -- Switch lookup function
-     [CoreToDo],                       -- Core-to-core spec
-#ifdef DPH 
-     [PodizeToDo],                     -- Podizer spec
-     [CoreToDo],                       -- post podized Core-to-core spec 
-#endif
-     [StgToDo]                         -- Stg-to-stg spec
-    )
-
 data SwitchResult
-  = SwBool     Bool    -- on/off
-  | SwString   String  -- nothing or a String
-  | SwInt      Int     -- nothing or an Int
+  = SwBool     Bool            -- on/off
+  | SwString   FAST_STRING     -- nothing or a String
+  | SwInt      Int             -- nothing or an Int
 \end{code}
 
 \begin{code}
@@ -81,889 +187,570 @@ data CoreToDo            -- These are diff core-to-core passes,
        (SimplifierSwitch -> SwitchResult)
                        -- Each run of the simplifier can take a different
                        -- set of simplifier-specific flags.
-
-  | CoreDoArityAnalysis -- UNUSED right now
-  | CoreDoCalcInlinings1
-  | CoreDoCalcInlinings2
   | CoreDoFloatInwards
-  | CoreDoFullLaziness
+  | CoreDoFloatOutwards Bool   -- True <=> float lambdas to top level
   | CoreLiberateCase
   | CoreDoPrintCore
   | CoreDoStaticArgs
   | CoreDoStrictness
+  | CoreDoWorkerWrapper
   | CoreDoSpecialising
-  | CoreDoDeforest
-  | CoreDoAutoCostCentres
-  | CoreDoFoldrBuildWorkerWrapper
-  | CoreDoFoldrBuildWWAnal
--- ANDY:
---| CoreDoHaskPrint
---| CoreDoHaskLetlessPrint
+  | CoreDoSpecConstr
+  | CoreDoUSPInf
+  | CoreDoCPResult
+  | CoreDoGlomBinds
+  | CoreCSE
+
+  | CoreDoNothing       -- useful when building up lists of these things
 \end{code}
 
 \begin{code}
 data StgToDo
-  = StgDoStaticArgs
-  | StgDoUpdateAnalysis
-  | StgDoLambdaLift
-  | StgDoMassageForProfiling  -- should be (next to) last
+  = StgDoMassageForProfiling  -- should be (next to) last
   -- There's also setStgVarInfo, but its absolute "lastness"
   -- is so critical that it is hardwired in (no flag).
   | D_stg_stats
 \end{code}
 
 \begin{code}
-#ifdef DPH
-data PodizeToDo
-  = PodizeNeeded Int           -- Which dimensioned PODs need vectorizing
-#endif {- Data Parallel Haskell -}
+data SimplifierSwitch
+  = MaxSimplifierIterations Int
+  | SimplInlinePhase Int
+  | DontApplyRules
+  | NoCaseOfCase
+  | SimplLetToCase
 \end{code}
 
-@GlobalSwitches@ may be visible everywhere in the compiler.
-@SimplifierSwitches@ (which follow) are visible only in the main
-Core-to-Core simplifier.
+%************************************************************************
+%*                                                                     *
+\subsection{Dynamic command-line options}
+%*                                                                     *
+%************************************************************************
 
 \begin{code}
-data GlobalSwitch
-  = ProduceC   String  -- generate C output into this file
-  | ProduceS   String  -- generate native-code assembler into this file
-  | ProduceHi  String  -- generate .hi interface  into this file
---UNUSED:  | ProduceHu String  -- generate .hu usage-info into this file
-
-  | AsmTarget  String  -- architecture we are generating code for
-  | ForConcurrent
-
-  | Haskell_1_3                -- if set => Haskell 1.3; else 1.2
-  | GlasgowExts                -- Glasgow Haskell extensions allowed
-  | CompilingPrelude   -- Compiling prelude source
-
-  | HideBuiltinNames   -- fiddle builtin namespace; used for compiling Prelude
-  | HideMostBuiltinNames
-  | EnsureSplittableC String -- (by globalising all top-level Ids w/ this String)
-
-  | Verbose
-  | PprStyle_User      -- printing "level" (mostly for debugging)
-  | PprStyle_Debug
-  | PprStyle_All
-
-  | DoCoreLinting      -- paranoia flags
-  | EmitArityChecks
-
-  | OmitInterfacePragmas
-  | OmitDerivedRead
-  | OmitReexportedInstances
-
-  | UnfoldingUseThreshold      Int  -- global one; see also SimplUnf...
-  | UnfoldingCreationThreshold Int  -- ditto
-  | UnfoldingOverrideThreshold Int
-
-  | ReportWhyUnfoldingsDisallowed
-  | UseGetMentionedVars
-  | ShowPragmaNameErrs
-  | NameShadowingNotOK
-  | SigsRequired
-
-  | SccProfilingOn
-  | AutoSccsOnExportedToplevs
-  | AutoSccsOnAllToplevs
-  | AutoSccsOnIndividualCafs
---UNUSED:  | AutoSccsOnIndividualDicts
-  | SccGroup String    -- name of "group" for this cost centres in this module
-
-  | DoTickyProfiling
-
-  | DoSemiTagging
-
-  -- ToDo: turn these into SimplifierSwitches?
-  | FoldrBuildOn       -- If foldr/build-style transformations are on.
-                       -- See also SimplDoFoldrBuild, which is used
-                       -- inside the simplifier.
-  | FoldrBuildTrace    -- show all foldr/build optimisations.
-
-  | SpecialiseImports     -- Treat non-essential spec requests as errors
-  | ShowImportSpecs       -- Output spec requests for non-essential specs
-  | OmitUnspecialisedCode  -- ToDo? (Patrick)
-  | SpecialiseOverloaded
-  | SpecialiseUnboxed
-  | SpecialiseAll
-  | SpecialiseTrace
-
-  -- this batch of flags is for particular experiments;
-  -- v unlikely to be used in any other circumstance
---UNUSED:  | OmitStkChecks
-  | OmitBlackHoling
-  | StgDoLetNoEscapes
-  | IgnoreStrictnessPragmas -- ToDo: still useful?
-  | IrrefutableTuples      -- We inject extra "LazyPat"s in the typechecker
-  | IrrefutableEverything   -- (TcPat); doing it any earlier would mean that
-                           -- deriving-generated code wouldn't be irrefutablified.
-  | AllStrict
-  | NumbersStrict
-  | AllDemanded
-
-  | ReturnInRegsThreshold   Int
-  | VectoredReturnThreshold Int -- very likely UNUSED
-
--- NOT REALLY USED:  | D_dump_type_info        -- for Robin Popplestone stuff
-
-  | D_dump_rif2hs      -- debugging: print out various things
-  | D_dump_rn4
-  | D_dump_tc
-  | D_dump_deriv
-  | D_dump_ds
-  | D_dump_occur_anal
-  | D_dump_simpl
-  | D_dump_spec
-  | D_dump_stranal
-  | D_dump_deforest
-  | D_dump_stg
-  | D_dump_absC
-  | D_dump_flatC
-  | D_dump_realC
-  | D_dump_asm
-  | D_dump_core_passes         -- A Gill-ism
-  | D_dump_core_passes_info    -- Yet another Gill-ism
-
-  | D_verbose_core2core
-  | D_verbose_stg2stg
-  | D_simplifier_stats
-
-{- ????
-  | Extra__Flag1
-  | Extra__Flag2
-  | Extra__Flag3
-  | Extra__Flag4
-  | Extra__Flag5
-  | Extra__Flag6
-  | Extra__Flag7
-  | Extra__Flag8
-  | Extra__Flag9
+data DynFlag
+
+   -- debugging flags
+   = Opt_D_dump_absC
+   | Opt_D_dump_asm
+   | Opt_D_dump_cpranal
+   | Opt_D_dump_deriv
+   | Opt_D_dump_ds
+   | Opt_D_dump_flatC
+   | Opt_D_dump_foreign
+   | Opt_D_dump_inlinings
+   | Opt_D_dump_occur_anal
+   | Opt_D_dump_parsed
+   | Opt_D_dump_realC
+   | Opt_D_dump_rn
+   | Opt_D_dump_simpl
+   | Opt_D_dump_simpl_iterations
+   | Opt_D_dump_spec
+   | Opt_D_dump_sat
+   | Opt_D_dump_stg
+   | Opt_D_dump_stranal
+   | Opt_D_dump_tc
+   | Opt_D_dump_types
+   | Opt_D_dump_rules
+   | Opt_D_dump_usagesp
+   | Opt_D_dump_cse
+   | Opt_D_dump_worker_wrapper
+   | Opt_D_dump_rn_trace
+   | Opt_D_dump_rn_stats
+   | Opt_D_dump_stix
+   | Opt_D_dump_simpl_stats
+   | Opt_D_dump_tc_trace
+   | Opt_D_dump_BCOs
+   | Opt_D_source_stats
+   | Opt_D_verbose_core2core
+   | Opt_D_verbose_stg2stg
+   | Opt_D_dump_hi
+   | Opt_D_dump_hi_diffs
+   | Opt_D_dump_minimal_imports
+   | Opt_DoCoreLinting
+   | Opt_DoStgLinting
+   | Opt_DoUSPLinting
+
+   | Opt_WarnDuplicateExports
+   | Opt_WarnHiShadows
+   | Opt_WarnIncompletePatterns
+   | Opt_WarnMissingFields
+   | Opt_WarnMissingMethods
+   | Opt_WarnMissingSigs
+   | Opt_WarnNameShadowing
+   | Opt_WarnOverlappingPatterns
+   | Opt_WarnSimplePatterns
+   | Opt_WarnTypeDefaults
+   | Opt_WarnUnusedBinds
+   | Opt_WarnUnusedImports
+   | Opt_WarnUnusedMatches
+   | Opt_WarnDeprecations
+   | Opt_WarnMisc
+
+   -- language opts
+   | Opt_AllowOverlappingInstances
+   | Opt_AllowUndecidableInstances
+   | Opt_GlasgowExts
+   | Opt_Generics
+   | Opt_NoImplicitPrelude 
+
+   deriving (Eq)
+
+data DynFlags = DynFlags {
+  coreToDo             :: [CoreToDo],
+  stgToDo              :: [StgToDo],
+  hscLang              :: HscLang,
+  hscOutName           :: String,      -- name of the output file
+  hscStubHOutName      :: String,      -- name of the .stub_h output file
+  hscStubCOutName      :: String,      -- name of the .stub_c output file
+  extCoreName          :: String,      -- name of the .core output file
+  verbosity            :: Int,         -- verbosity level
+  cppFlag              :: Bool,        -- preprocess with cpp?
+  stolen_x86_regs      :: Int,         
+  cmdlineHcIncludes    :: [String],    -- -#includes
+
+  -- options for particular phases
+  opt_L                        :: [String],
+  opt_P                        :: [String],
+  opt_c                        :: [String],
+  opt_a                        :: [String],
+  opt_m                        :: [String],
+
+  -- hsc dynamic flags
+  flags                :: [DynFlag]
+ }
+
+data HscLang
+  = HscC
+  | HscAsm
+  | HscJava
+  | HscILX
+  | HscInterpreted
+    deriving (Eq, Show)
+
+defaultDynFlags = DynFlags {
+  coreToDo = [], stgToDo = [], 
+  hscLang = HscC, 
+  hscOutName = "", 
+  hscStubHOutName = "", hscStubCOutName = "",
+  extCoreName = "",
+  verbosity = 0, 
+  cppFlag              = False,
+  stolen_x86_regs      = 4,
+  cmdlineHcIncludes    = [],
+  opt_L                        = [],
+  opt_P                        = [],
+  opt_c                        = [],
+  opt_a                        = [],
+  opt_m                        = [],
+  flags = standardWarnings,
+  }
+
+{- 
+    Verbosity levels:
+       
+    0  |   print errors & warnings only
+    1   |   minimal verbosity: print "compiling M ... done." for each module.
+    2   |   equivalent to -dshow-passes
+    3   |   equivalent to existing "ghc -v"
+    4   |   "ghc -v -ddump-most"
+    5   |   "ghc -v -ddump-all"
 -}
 
-#ifdef DPH
-  | PodizeIntelligent
-  | PodizeAggresive
-  | PodizeVeryAggresive
-  | PodizeExtremelyAggresive
-  | D_dump_pod
-  | D_dump_psimpl
-  | D_dump_nextC
-#endif {- Data Parallel Haskell -}
-\end{code}
+dopt :: DynFlag -> DynFlags -> Bool
+dopt f dflags  = f `elem` (flags dflags)
 
-\begin{code}
-data SimplifierSwitch
-  = SimplOkToDupCode
-  | SimplFloatLetsExposingWHNF
-  | SimplOkToFloatPrimOps
-  | SimplAlwaysFloatLetsFromLets
-  | SimplDoCaseElim
-  | SimplReuseCon
-  | SimplCaseOfCase
-  | SimplLetToCase
---UNUSED:  | SimplOkToInlineInLambdas
-  | SimplMayDeleteConjurableIds
-  | SimplPedanticBottoms -- see Simplifier for an explanation
-  | SimplDoArityExpand  -- expand arity of bindings
-  | SimplDoFoldrBuild   -- This is the per-simplification flag;
-                        -- see also FoldrBuildOn, used elsewhere
-                        -- in the compiler.
-  | SimplDoNewOccurAnal         --  use the *new*, all singing, Occurance analysis
-  | SimplDoInlineFoldrBuild
-                        -- inline foldr/build (*after* f/b rule is used)
-
-  | IgnoreINLINEPragma
-  | SimplDoLambdaEtaExpansion
---UNUSED:  | SimplDoMonadEtaExpansion
-
-  | SimplDoEtaReduction
+dopt_CoreToDo :: DynFlags -> [CoreToDo]
+dopt_CoreToDo = coreToDo
 
-  | EssentialUnfoldingsOnly -- never mind the thresholds, only
-                           -- do unfoldings that *must* be done
-                           -- (to saturate constructors and primitives)
+dopt_StgToDo :: DynFlags -> [StgToDo]
+dopt_StgToDo = stgToDo
 
-  | ShowSimplifierProgress  -- report counts on every interation
+dopt_OutName :: DynFlags -> String
+dopt_OutName = hscOutName
 
-  | MaxSimplifierIterations Int
+dopt_HscLang :: DynFlags -> HscLang
+dopt_HscLang = hscLang
 
-  | SimplUnfoldingUseThreshold      Int -- per-simplification variants
-  | SimplUnfoldingCreationThreshold Int
+dopt_set :: DynFlags -> DynFlag -> DynFlags
+dopt_set dfs f = dfs{ flags = f : flags dfs }
 
-  | KeepSpecPragmaIds      -- We normally *toss* Ids we can do without
-  | KeepUnusedBindings
-
-  | SimplNoLetFromCase     -- used when turning off floating entirely
-  | SimplNoLetFromApp      -- (for experimentation only) WDP 95/10
-  | SimplNoLetFromStrictLet
-{-
-  | Extra__SimplFlag1
-  | Extra__SimplFlag2
-  | Extra__SimplFlag3
-  | Extra__SimplFlag4
-  | Extra__SimplFlag5
-  | Extra__SimplFlag6
-  | Extra__SimplFlag7
-  | Extra__SimplFlag8
--}
+dopt_unset :: DynFlags -> DynFlag -> DynFlags
+dopt_unset dfs f = dfs{ flags = filter (/= f) (flags dfs) }
 \end{code}
 
-%************************************************************************
-%*                                                                     *
-\subsection[CmdLineOpts-classify]{Classifying command-line options}
-%*                                                                     *
-%************************************************************************
+-----------------------------------------------------------------------------
+-- Mess about with the mutable variables holding the dynamic arguments
 
-\begin{code}
-classifyOpts :: [String]           -- cmd-line args, straight from GetArgs
-            -> MainIO CmdLineInfo
--- The MainIO bit is because we might find an unknown flag
--- in which case we print an error message
-
-#ifndef DPH
-classifyOpts opts
-  = sep opts [] [] [] -- accumulators...
-  where
-    sep :: [String]                             -- cmd-line opts (input)
-       -> [GlobalSwitch]                        -- switch accumulator
-       -> [CoreToDo] -> [StgToDo]               -- to_do accumulators
-       -> MainIO CmdLineInfo                    -- result
-
-    sep [] glob_sw core_td stg_td
-      = returnMn (
-         isAmong glob_sw,
-         reverse core_td,
-         reverse stg_td
-       )
-
-    sep (opt1:opts) glob_sw core_td stg_td
-
-#else {- Data Parallel Haskell -}
-classifyOpts opts
-  = sep opts [] [] [] [] [] -- accumulators...
-  where
-    sep :: [String]                             -- cmd-line opts (input)
-       -> [GlobalSwitch]                        -- switch accumulator
-       -> [CoreToDo] -> [PodizeToDo]            -- to_do accumulators
-       -> [CoreToDo] -> [StgToDo]
-       -> MainIO CmdLineInfo                    -- result
-
-    -- see also the related "simpl_sep" function, used
-    -- to collect up the SimplifierSwitches for a "-fsimplify".
-
-    sep [] glob_sw core_td pod_td pcore_td stg_td
-      = returnMn (
-         isAmong glob_sw,
-         reverse core_td,
-         reverse pod_td,
-         reverse pcore_td,
-         reverse stg_td
-       )
-
-    sep (opt1:opts) glob_sw core_td pod_td pcore_td stg_td
-#endif {- Data Parallel Haskell -}
-
-#ifndef DPH
-#define GLOBAL_SW(switch)   sep opts (switch:glob_sw) core_td stg_td
-#define CORE_TD(to_do)     sep opts glob_sw (to_do:core_td) stg_td
-#define POD_TD(to_do)       sep opts glob_sw core_td stg_td
-#define PAR_CORE_TD(to_do)  sep opts glob_sw core_td stg_td
-#define BOTH_CORE_TD(to_do) sep opts glob_sw (to_do:core_td) stg_td
-#define STG_TD(to_do)      sep opts glob_sw core_td (to_do:stg_td)
-#define IGNORE_ARG()       sep opts glob_sw core_td stg_td
+-- v_InitDynFlags 
+--     is the "baseline" dynamic flags, initialised from
+--     the defaults and command line options, and updated by the
+--     ':s' command in GHCi.
+--
+-- v_DynFlags
+--     is the dynamic flags for the current compilation.  It is reset
+--     to the value of v_InitDynFlags before each compilation, then
+--     updated by reading any OPTIONS pragma in the current module.
 
-#else
+\begin{code}
+GLOBAL_VAR(v_InitDynFlags, defaultDynFlags, DynFlags)
+GLOBAL_VAR(v_DynFlags,     defaultDynFlags, DynFlags)
 
-#define GLOBAL_SW(switch) sep opts (switch:glob_sw) core_td pod_td pcore_td stg_td
-#define CORE_TD(to_do)   sep opts glob_sw (to_do:core_td) pod_td pcore_td stg_td
-#define POD_TD(to_do)    sep opts glob_sw core_td (to_do:pod_td) pcore_td stg_td
-#define PAR_CORE_TD(do)          sep opts glob_sw core_td pod_td (do:pcore_td) stg_td
-#define BOTH_CORE_TD(do)  sep opts glob_sw (do:core_td) pod_td (do:pcore_td) stg_td
-#define STG_TD(to_do)    sep opts glob_sw core_td pod_td pcore_td (to_do:stg_td)
-#define IGNORE_ARG()     sep opts glob_sw core_td pod_td pcore_td stg_td
-
-#endif {- Data Parallel Haskell -}
-
--- ToDo: DPH-ify
-#define GLOBAL_SIMPL_SW(switch) simpl_sep opts (switch:simpl_sw) glob_sw core_td stg_td
-
-      = let
-           maybe_fasm          = starts_with "-fasm-"  opt1
-           maybe_G             = starts_with "-G"      opt1
-           maybe_C             = starts_with "-C"      opt1
-           maybe_S             = starts_with "-S"      opt1
-           maybe_hi            = starts_with "-hi"     opt1
-           maybe_hu            = starts_with "-hu"     opt1
-           maybe_uut           = starts_with "-funfolding-use-threshold"      opt1
-           maybe_uct           = starts_with "-funfolding-creation-threshold" opt1
-           maybe_uot           = starts_with "-funfolding-override-threshold" opt1
-           maybe_rirt          = starts_with "-freturn-in-regs-threshold"     opt1
-           maybe_gtn           = starts_with "-fglobalise-toplev-names"       opt1
-           starts_with_fasm    = maybeToBool maybe_fasm
-           starts_with_G       = maybeToBool maybe_G
-           starts_with_C       = maybeToBool maybe_C
-           starts_with_S       = maybeToBool maybe_S
-           starts_with_hi      = maybeToBool maybe_hi
-           starts_with_hu      = maybeToBool maybe_hu
-           starts_with_uut     = maybeToBool maybe_uut
-           starts_with_uct     = maybeToBool maybe_uct
-           starts_with_uot     = maybeToBool maybe_uot
-           starts_with_rirt    = maybeToBool maybe_rirt
-           starts_with_gtn     = maybeToBool maybe_gtn
-           (Just after_fasm)   = maybe_fasm
-           (Just after_G)      = maybe_G
-           (Just after_C)      = maybe_C
-           (Just after_S)      = maybe_S
-           (Just after_hi)     = maybe_hi
-           (Just after_hu)     = maybe_hu
-           (Just after_uut)    = maybe_uut
-           (Just after_uct)    = maybe_uct
-           (Just after_uot)    = maybe_uot
-           (Just after_rirt)   = maybe_rirt
-           (Just after_gtn)    = maybe_gtn
-       in
-       case opt1 of -- the non-"just match a string" options are at the end...
-         ',' : _          -> IGNORE_ARG() -- it is for the parser
-         "-ddump-rif2hs"  -> GLOBAL_SW(D_dump_rif2hs)
-         "-ddump-rn4"     -> GLOBAL_SW(D_dump_rn4)
-         "-ddump-tc"      -> GLOBAL_SW(D_dump_tc)
-         "-ddump-deriv"   -> GLOBAL_SW(D_dump_deriv)
-         "-ddump-ds"      -> GLOBAL_SW(D_dump_ds)
-         "-ddump-stranal" -> GLOBAL_SW(D_dump_stranal)
-         "-ddump-deforest"-> GLOBAL_SW(D_dump_deforest)
-         "-ddump-spec"    -> GLOBAL_SW(D_dump_spec)
-         "-ddump-simpl"   -> GLOBAL_SW(D_dump_simpl)
-         "-ddump-occur-anal" -> GLOBAL_SW(D_dump_occur_anal)
--- NOT REALLY USED:      "-ddump-type-info"  -> GLOBAL_SW(D_dump_type_info)
-#ifdef DPH
-         "-ddump-pod"   ->   GLOBAL_SW(D_dump_pod)
-         "-ddump-psimpl"->   GLOBAL_SW(D_dump_psimpl)
-         "-ddump-nextC" ->   GLOBAL_SW(D_dump_nextC)
-#endif {- Data Parallel Haskell -}
-
-         "-ddump-stg"  ->    GLOBAL_SW(D_dump_stg)
-         "-ddump-absC" ->    GLOBAL_SW(D_dump_absC)
-         "-ddump-flatC"->    GLOBAL_SW(D_dump_flatC)
-         "-ddump-realC"->    GLOBAL_SW(D_dump_realC)
-          "-ddump-asm"  ->    GLOBAL_SW(D_dump_asm)
-
-          "-ddump-core-passes"      -> GLOBAL_SW(D_dump_core_passes)
--- ANDY:  "-ddump-haskell"         -> GLOBAL_SW(D_dump_core_passes_info)
-         "-dsimplifier-stats"      -> GLOBAL_SW(D_simplifier_stats)
-
-         "-dverbose-simpl" ->GLOBAL_SW(D_verbose_core2core)
-         "-dverbose-stg" ->  GLOBAL_SW(D_verbose_stg2stg)
-
-         "-fuse-get-mentioned-vars" -> GLOBAL_SW(UseGetMentionedVars)
-
-         "-fhaskell-1.3"               -> GLOBAL_SW(Haskell_1_3)
-         "-dcore-lint"                 -> GLOBAL_SW(DoCoreLinting)
-         "-fomit-interface-pragmas"    -> GLOBAL_SW(OmitInterfacePragmas)
-         "-fignore-strictness-pragmas" -> GLOBAL_SW(IgnoreStrictnessPragmas)
-         "-firrefutable-tuples"        -> GLOBAL_SW(IrrefutableTuples)
-         "-firrefutable-everything"    -> GLOBAL_SW(IrrefutableEverything)
-         "-fall-strict"                -> GLOBAL_SW(AllStrict)
-         "-fnumbers-strict"            -> GLOBAL_SW(NumbersStrict)
-         "-fall-demanded"              -> GLOBAL_SW(AllDemanded)
-
-         "-fsemi-tagging"   -> GLOBAL_SW(DoSemiTagging)
-
-         "-fsimplify"       -> -- gather up SimplifierSwitches specially...
-                               simpl_sep opts [] glob_sw core_td stg_td
-
---UNUSED: "-farity-analysis" -> CORE_TD(CoreDoArityAnalysis)
-         "-fcalc-inlinings1"-> CORE_TD(CoreDoCalcInlinings1)
-         "-fcalc-inlinings2"-> CORE_TD(CoreDoCalcInlinings2)
-         "-ffloat-inwards"  -> CORE_TD(CoreDoFloatInwards)
-         "-ffull-laziness"  -> CORE_TD(CoreDoFullLaziness)
-          "-fliberate-case"  -> CORE_TD(CoreLiberateCase)
-          "-fprint-core"     -> CORE_TD(CoreDoPrintCore)
-         "-fstatic-args"    -> CORE_TD(CoreDoStaticArgs)
-         "-fstrictness"     -> CORE_TD(CoreDoStrictness)
-         "-fspecialise"     -> CORE_TD(CoreDoSpecialising)
-         "-fdeforest"       -> CORE_TD(CoreDoDeforest)
-         "-fadd-auto-sccs"  -> CORE_TD(CoreDoAutoCostCentres)
-         "-ffoldr-build-worker-wrapper"  -> CORE_TD(CoreDoFoldrBuildWorkerWrapper)
-         "-ffoldr-build-ww-anal"  -> CORE_TD(CoreDoFoldrBuildWWAnal)
---ANDY:   "-fprint-haskell-core" -> CORE_TD(CoreDoHaskPrint)
---        "-fprint-haskell-letless-core" -> CORE_TD(CoreDoHaskLetlessPrint)
-
-         "-fspecialise-overloaded" -> GLOBAL_SW(SpecialiseOverloaded)
-         "-fspecialise-unboxed"    -> GLOBAL_SW(SpecialiseUnboxed)
-         "-fspecialise-all"        -> GLOBAL_SW(SpecialiseAll)
-         "-fspecialise-imports"    -> GLOBAL_SW(SpecialiseImports)
-         "-fshow-import-specs"     -> GLOBAL_SW(ShowImportSpecs)
-         "-ftrace-specialisation"  -> GLOBAL_SW(SpecialiseTrace)
-
-         "-freport-disallowed-unfoldings"
-                            -> GLOBAL_SW(ReportWhyUnfoldingsDisallowed)
-
-         "-fomit-derived-read" -> GLOBAL_SW(OmitDerivedRead)
-
-          "-ffoldr-build-on"       -> GLOBAL_SW(FoldrBuildOn)
-          "-ffoldr-build-trace"            -> GLOBAL_SW(FoldrBuildTrace)
-
-         "-fstg-static-args" -> STG_TD(StgDoStaticArgs)
-         "-fupdate-analysis" -> STG_TD(StgDoUpdateAnalysis)
-         "-dstg-stats"       -> STG_TD(D_stg_stats)
-         "-flambda-lift"     -> STG_TD(StgDoLambdaLift)
-         "-fmassage-stg-for-profiling" -> STG_TD(StgDoMassageForProfiling)
-
-         "-flet-no-escape"   -> GLOBAL_SW(StgDoLetNoEscapes)
-
-#ifdef DPH
-         "-fpodize-vector"              -> POD_TD(PodizeNeeded 1)
-         "-fpodize-matrix"              -> POD_TD(PodizeNeeded 2)
-         "-fpodize-cube"                -> POD_TD(PodizeNeeded 3)
-         "-fpodize-intelligent"         -> GLOBAL_SW(PodizeIntelligent)
-         "-fpodize-aggresive"           -> GLOBAL_SW(PodizeAggresive)
-         "-fpodize-very-aggresive"      -> GLOBAL_SW(PodizeVeryAggresive)
-         "-fpodize-extremely-aggresive" -> GLOBAL_SW(PodizeExtremelyAggresive)
-#endif {- Data Parallel Haskell -}
-
-         "-v"          ->          GLOBAL_SW(Verbose)
-
-         "-fglasgow-exts" ->       GLOBAL_SW(GlasgowExts)
-         "-prelude"    ->          GLOBAL_SW(CompilingPrelude)
-
-         "-fscc-profiling"                 -> GLOBAL_SW(SccProfilingOn)
-         "-fauto-sccs-on-exported-toplevs" -> GLOBAL_SW(AutoSccsOnExportedToplevs)
-         "-fauto-sccs-on-all-toplevs"      -> GLOBAL_SW(AutoSccsOnAllToplevs)
-         "-fauto-sccs-on-individual-cafs"  -> GLOBAL_SW(AutoSccsOnIndividualCafs)
---UNUSED: "-fauto-sccs-on-individual-dicts" -> GLOBAL_SW(AutoSccsOnIndividualDicts)
-
-         "-fticky-ticky"  -> GLOBAL_SW(DoTickyProfiling)
-
-         "-dppr-user"  ->          GLOBAL_SW(PprStyle_User)
-         "-dppr-debug" ->          GLOBAL_SW(PprStyle_Debug)
-         "-dppr-all"   ->          GLOBAL_SW(PprStyle_All)
-
-         "-fhide-builtin-names"->      GLOBAL_SW(HideBuiltinNames)
-         "-fmin-builtin-names" ->      GLOBAL_SW(HideMostBuiltinNames)
-
-         "-fconcurrent"            -> GLOBAL_SW(ForConcurrent)
-
-         "-fomit-unspecialised-code" -> GLOBAL_SW(OmitUnspecialisedCode)
-         "-fshow-pragma-name-errs" -> GLOBAL_SW(ShowPragmaNameErrs)
-         "-fname-shadowing-not-ok" -> GLOBAL_SW(NameShadowingNotOK)
-         "-fsignatures-required"   -> GLOBAL_SW(SigsRequired)
-         "-fomit-reexported-instances" -> GLOBAL_SW(OmitReexportedInstances)
-         "-darity-checks"  -> GLOBAL_SW(EmitArityChecks)
---UNUSED:        "-dno-stk-chks"   -> GLOBAL_SW(OmitStkChecks)
-         "-dno-black-holing"-> GLOBAL_SW(OmitBlackHoling)
-
-         _ | starts_with_fasm -> GLOBAL_SW(AsmTarget after_fasm)
-           | starts_with_G    -> GLOBAL_SW(SccGroup  after_G)  -- profiling "group"
-           | starts_with_C    -> GLOBAL_SW(ProduceC  after_C)  -- main C output 
-           | starts_with_S    -> GLOBAL_SW(ProduceS  after_S)  -- main .s output 
-           | starts_with_hi   -> GLOBAL_SW(ProduceHi after_hi) -- interface 
---UNUSED:   | starts_with_hu   -> GLOBAL_SW(ProduceHu after_hu)        -- usage info
-
-           | starts_with_uut  -> GLOBAL_SW(UnfoldingUseThreshold      (read after_uut))
-           | starts_with_uct  -> GLOBAL_SW(UnfoldingCreationThreshold (read after_uct))
-           | starts_with_uot  -> GLOBAL_SW(UnfoldingOverrideThreshold (read after_uot))
-
-           | starts_with_rirt -> -- trace ("rirt:"++after_rirt) $
-                                 GLOBAL_SW(ReturnInRegsThreshold (read after_rirt))
-
-           | starts_with_gtn  -> GLOBAL_SW(EnsureSplittableC after_gtn)
-
-
-         _ -> writeMn stderr ("*** WARNING: bad option: "++opt1++"\n") `thenMn` ( \ _ ->
-               -- NB: the driver is really supposed to handle bad options
-              IGNORE_ARG() )
-
-    ----------------
-
-    starts_with :: String -> String -> Maybe String
-
-    starts_with []     str = Just str
-    starts_with (c:cs) (s:ss)
-      = if c /= s then Nothing else starts_with cs ss
+setDynFlags :: DynFlags -> IO ()
+setDynFlags dfs = writeIORef v_DynFlags dfs
 
-    ----------------
+saveDynFlags :: IO ()
+saveDynFlags = do dfs <- readIORef v_DynFlags
+                 writeIORef v_InitDynFlags dfs
 
-    -- ToDo: DPH-ify "simpl_sep"!
+restoreDynFlags :: IO DynFlags
+restoreDynFlags = do dfs <- readIORef v_InitDynFlags
+                    writeIORef v_DynFlags dfs
+                    return dfs
 
-    simpl_sep :: [String]                      -- cmd-line opts (input)
-       -> [SimplifierSwitch]                   -- simplifier-switch accumulator
-       -> [GlobalSwitch]                       -- switch accumulator
-       -> [CoreToDo] -> [StgToDo]              -- to_do accumulators
-       -> MainIO CmdLineInfo                   -- result
+getDynFlags :: IO DynFlags
+getDynFlags = readIORef v_DynFlags
 
-       -- "simpl_sep" tailcalls "sep" once it's seen one set
-       -- of SimplifierSwitches for a CoreDoSimplify.
+updDynFlags :: (DynFlags -> DynFlags) -> IO ()
+updDynFlags f = do dfs <- readIORef v_DynFlags
+                  writeIORef v_DynFlags (f dfs)
 
-#ifdef DEBUG
-    simpl_sep input@[] simpl_sw glob_sw core_td stg_td
-      = panic "simpl_sep []"
-#endif
+dynFlag :: (DynFlags -> a) -> IO a
+dynFlag f = do dflags <- readIORef v_DynFlags; return (f dflags)
 
-       -- The SimplifierSwitches should be delimited by "(" and ")".
-
-    simpl_sep ("(":opts) [{-better be empty-}] glob_sw core_td stg_td
-      = simpl_sep opts [] glob_sw core_td stg_td
-
-    simpl_sep (")":opts) simpl_sw glob_sw core_td stg_td
-      = let
-           this_CoreDoSimplify = CoreDoSimplify (isAmongSimpl simpl_sw)
-       in
-       sep opts glob_sw (this_CoreDoSimplify : core_td) stg_td
-
-    simpl_sep (opt1:opts) simpl_sw glob_sw core_td stg_td
-      = let
-           maybe_suut          = starts_with "-fsimpl-uf-use-threshold"      opt1
-           maybe_suct          = starts_with "-fsimpl-uf-creation-threshold" opt1
-           maybe_msi           = starts_with "-fmax-simplifier-iterations"   opt1
-           starts_with_suut    = maybeToBool maybe_suut
-           starts_with_suct    = maybeToBool maybe_suct
-           starts_with_msi     = maybeToBool maybe_msi
-           (Just after_suut)   = maybe_suut
-           (Just after_suct)   = maybe_suct
-           (Just after_msi)    = maybe_msi
-       in
-       case opt1 of -- the non-"just match a string" options are at the end...
-         "-fshow-simplifier-progress" -> GLOBAL_SIMPL_SW(ShowSimplifierProgress)
-
-         "-fcode-duplication-ok" -> GLOBAL_SIMPL_SW(SimplOkToDupCode)
-         "-ffloat-lets-exposing-whnf"  -> GLOBAL_SIMPL_SW(SimplFloatLetsExposingWHNF)
-         "-ffloat-primops-ok"  -> GLOBAL_SIMPL_SW(SimplOkToFloatPrimOps)
-         "-falways-float-lets-from-lets" -> GLOBAL_SIMPL_SW(SimplAlwaysFloatLetsFromLets)
-         "-fdo-case-elim" -> GLOBAL_SIMPL_SW(SimplDoCaseElim)
-         "-fdo-eta-reduction" -> GLOBAL_SIMPL_SW(SimplDoEtaReduction)
-         "-fdo-lambda-eta-expansion" -> GLOBAL_SIMPL_SW(SimplDoLambdaEtaExpansion)
---UNUSED:        "-fdo-monad-eta-expansion" -> GLOBAL_SIMPL_SW(SimplDoMonadEtaExpansion)
-         "-fdo-foldr-build"  -> GLOBAL_SIMPL_SW(SimplDoFoldrBuild)
-         "-fdo-new-occur-anal"  -> GLOBAL_SIMPL_SW(SimplDoNewOccurAnal)
-         "-fdo-arity-expand"  -> GLOBAL_SIMPL_SW(SimplDoArityExpand)
-         "-fdo-inline-foldr-build"  -> GLOBAL_SIMPL_SW(SimplDoInlineFoldrBuild)
-         "-freuse-con"       -> GLOBAL_SIMPL_SW(SimplReuseCon)
-         "-fcase-of-case"    ->    GLOBAL_SIMPL_SW(SimplCaseOfCase)
-         "-flet-to-case"     -> GLOBAL_SIMPL_SW(SimplLetToCase)
-         "-fpedantic-bottoms" -> GLOBAL_SIMPL_SW(SimplPedanticBottoms)
-         "-fkeep-spec-pragma-ids" -> GLOBAL_SIMPL_SW(KeepSpecPragmaIds)
-         "-fkeep-unused-bindings" -> GLOBAL_SIMPL_SW(KeepUnusedBindings)
---UNUSED:        "-finline-in-lambdas-ok" -> GLOBAL_SIMPL_SW(SimplOkToInlineInLambdas)
-         "-fmay-delete-conjurable-ids" -> GLOBAL_SIMPL_SW(SimplMayDeleteConjurableIds)
-         "-fessential-unfoldings-only" -> GLOBAL_SIMPL_SW(EssentialUnfoldingsOnly) 
-         "-fignore-inline-pragma"  -> GLOBAL_SIMPL_SW(IgnoreINLINEPragma)
-         "-fno-let-from-case"  -> GLOBAL_SIMPL_SW(SimplNoLetFromCase)
-         "-fno-let-from-app"  -> GLOBAL_SIMPL_SW(SimplNoLetFromApp)
-         "-fno-let-from-strict-let"  -> GLOBAL_SIMPL_SW(SimplNoLetFromStrictLet)
-
-         _ | starts_with_msi  -> GLOBAL_SIMPL_SW(MaxSimplifierIterations (read after_msi))
-           | starts_with_suut  -> GLOBAL_SIMPL_SW(SimplUnfoldingUseThreshold (read after_suut))
-           | starts_with_suct  -> GLOBAL_SIMPL_SW(SimplUnfoldingCreationThreshold (read after_suct))
-
-         _ -> writeMn stderr ("*** WARNING: bad simplifier option: "++opt1++"\n") `thenMn` ( \ _ ->
-               -- NB: the driver is really supposed to handle bad options
-              simpl_sep opts simpl_sw glob_sw core_td stg_td )
+setDynFlag, unSetDynFlag :: DynFlag -> IO ()
+setDynFlag f   = updDynFlags (\dfs -> dopt_set dfs f)
+unSetDynFlag f = updDynFlags (\dfs -> dopt_unset dfs f)
 \end{code}
 
+
 %************************************************************************
 %*                                                                     *
-\subsection[CmdLineOpts-order]{Switch ordering}
+\subsection{Warnings}
 %*                                                                     *
 %************************************************************************
 
-In spite of the @Produce*@ and @SccGroup@ constructors, these things
-behave just like enumeration types.
-
 \begin{code}
-instance Eq GlobalSwitch where
-    a == b = tagOf_Switch a _EQ_ tagOf_Switch b
-
-instance Ord GlobalSwitch where
-    a <  b  = tagOf_Switch a _LT_ tagOf_Switch b
-    a <= b  = tagOf_Switch a _LE_ tagOf_Switch b
+standardWarnings
+    = [ Opt_WarnDeprecations,
+       Opt_WarnOverlappingPatterns,
+       Opt_WarnMissingFields,
+       Opt_WarnMissingMethods,
+       Opt_WarnDuplicateExports
+      ]
+
+minusWOpts
+    = standardWarnings ++ 
+      [        Opt_WarnUnusedBinds,
+       Opt_WarnUnusedMatches,
+       Opt_WarnUnusedImports,
+       Opt_WarnIncompletePatterns,
+       Opt_WarnMisc
+      ]
+
+minusWallOpts
+    = minusWOpts ++
+      [        Opt_WarnTypeDefaults,
+       Opt_WarnNameShadowing,
+       Opt_WarnMissingSigs,
+       Opt_WarnHiShadows
+      ]
+\end{code}
 
-instance Eq SimplifierSwitch where
-    a == b = tagOf_SimplSwitch a _EQ_ tagOf_SimplSwitch b
+%************************************************************************
+%*                                                                     *
+\subsection{Classifying command-line options}
+%*                                                                     *
+%************************************************************************
 
-instance Ord SimplifierSwitch where
-    a <  b  = tagOf_SimplSwitch a _LT_ tagOf_SimplSwitch b
-    a <= b  = tagOf_SimplSwitch a _LE_ tagOf_SimplSwitch b
-
-tagOf_Switch (ProduceC _)              =(ILIT(0) :: FAST_INT)
-tagOf_Switch (ProduceS _)              = ILIT(1)
-tagOf_Switch (ProduceHi        _)              = ILIT(2)
---UNUSED:tagOf_Switch (ProduceHu       _)              = ILIT(3)
-tagOf_Switch (AsmTarget _)              = ILIT(4)
---UNUSED:tagOf_Switch ForParallel              = ILIT(5)
-tagOf_Switch ForConcurrent             = ILIT(6)
---UNUSED:tagOf_Switch ForGRIP                  = ILIT(7)
-tagOf_Switch Haskell_1_3               = ILIT(8)
-tagOf_Switch GlasgowExts               = ILIT(9)
-tagOf_Switch CompilingPrelude          = ILIT(10)
-tagOf_Switch HideBuiltinNames          = ILIT(11)
-tagOf_Switch HideMostBuiltinNames      = ILIT(12)
-tagOf_Switch (EnsureSplittableC _)     = ILIT(13)
-tagOf_Switch Verbose                   = ILIT(14)
-tagOf_Switch PprStyle_User             = ILIT(15)
-tagOf_Switch PprStyle_Debug            = ILIT(16)
-tagOf_Switch PprStyle_All              = ILIT(17)
-tagOf_Switch DoCoreLinting             = ILIT(18)
-tagOf_Switch EmitArityChecks           = ILIT(19)
-tagOf_Switch OmitInterfacePragmas      = ILIT(20)
-tagOf_Switch OmitDerivedRead           = ILIT(21)
-tagOf_Switch OmitReexportedInstances   = ILIT(22)
-tagOf_Switch (UnfoldingUseThreshold _)  = ILIT(23)
-tagOf_Switch (UnfoldingCreationThreshold _) = ILIT(24)
-tagOf_Switch (UnfoldingOverrideThreshold _) = ILIT(25)
-tagOf_Switch ReportWhyUnfoldingsDisallowed = ILIT(26)
-tagOf_Switch UseGetMentionedVars       = ILIT(27)
-tagOf_Switch ShowPragmaNameErrs                = ILIT(28)
-tagOf_Switch NameShadowingNotOK                = ILIT(29)
-tagOf_Switch SigsRequired              = ILIT(30)
-tagOf_Switch SccProfilingOn            = ILIT(31)
-tagOf_Switch AutoSccsOnExportedToplevs = ILIT(32)
-tagOf_Switch AutoSccsOnAllToplevs      = ILIT(33)
-tagOf_Switch AutoSccsOnIndividualCafs  = ILIT(34)
---UNUSED:tagOf_Switch AutoSccsOnIndividualDicts        = ILIT(35)
-tagOf_Switch (SccGroup _)              = ILIT(36)
-tagOf_Switch DoTickyProfiling          = ILIT(37)
-tagOf_Switch DoSemiTagging             = ILIT(38)
-tagOf_Switch FoldrBuildOn              = ILIT(39)
-tagOf_Switch FoldrBuildTrace           = ILIT(40)
-tagOf_Switch SpecialiseImports         = ILIT(41)
-tagOf_Switch ShowImportSpecs           = ILIT(42)
-tagOf_Switch OmitUnspecialisedCode     = ILIT(43)
-tagOf_Switch SpecialiseOverloaded      = ILIT(44)
-tagOf_Switch SpecialiseUnboxed         = ILIT(45)
-tagOf_Switch SpecialiseAll             = ILIT(46)
-tagOf_Switch SpecialiseTrace           = ILIT(47)
---UNUSED:tagOf_Switch OmitStkChecks            = ILIT(48)
-tagOf_Switch OmitBlackHoling           = ILIT(49)
-tagOf_Switch StgDoLetNoEscapes         = ILIT(50)
-tagOf_Switch IgnoreStrictnessPragmas   = ILIT(51)
-tagOf_Switch IrrefutableTuples         = ILIT(52)
-tagOf_Switch IrrefutableEverything     = ILIT(53)
-tagOf_Switch AllStrict                 = ILIT(54)
-tagOf_Switch NumbersStrict             = ILIT(55)
-tagOf_Switch AllDemanded               = ILIT(56)
--- NOT REALLY USED: tagOf_Switch D_dump_type_info              = ILIT(56)
-tagOf_Switch (ReturnInRegsThreshold _) = ILIT(57)
-tagOf_Switch (VectoredReturnThreshold _)= ILIT(58)
-tagOf_Switch D_dump_rif2hs             = ILIT(59)
-tagOf_Switch D_dump_rn4                        = ILIT(60)
-tagOf_Switch D_dump_tc                 = ILIT(61)
-tagOf_Switch D_dump_deriv              = ILIT(62)
-tagOf_Switch D_dump_ds                 = ILIT(63)
-tagOf_Switch D_dump_simpl              = ILIT(64)
-tagOf_Switch D_dump_spec               = ILIT(65)
-tagOf_Switch D_dump_occur_anal         = ILIT(66)
-tagOf_Switch D_dump_stranal            = ILIT(67)
-tagOf_Switch D_dump_stg                        = ILIT(68)
-tagOf_Switch D_dump_absC               = ILIT(69)
-tagOf_Switch D_dump_flatC              = ILIT(70)
-tagOf_Switch D_dump_realC              = ILIT(71)
-tagOf_Switch D_dump_asm                        = ILIT(72)
-tagOf_Switch D_dump_core_passes                = ILIT(73)
-tagOf_Switch D_dump_core_passes_info   = ILIT(74)
-tagOf_Switch D_verbose_core2core       = ILIT(75)
-tagOf_Switch D_verbose_stg2stg         = ILIT(76)
-tagOf_Switch D_simplifier_stats                = ILIT(77) {-see note below!-}
+\begin{code}
+-- v_Statis_hsc_opts is here to avoid a circular dependency with
+-- main/DriverState.
+GLOBAL_VAR(v_Static_hsc_opts, [], [String])
 
-{-
-tagOf_Switch Extra__Flag1              = ILIT(76)
-tagOf_Switch Extra__Flag2              = ILIT(77)
-tagOf_Switch Extra__Flag3              = ILIT(78)
-tagOf_Switch Extra__Flag4              = ILIT(79)
-tagOf_Switch Extra__Flag5              = ILIT(80)
-tagOf_Switch Extra__Flag6              = ILIT(81)
-tagOf_Switch Extra__Flag7              = ILIT(82)
-tagOf_Switch Extra__Flag8              = ILIT(83)
-tagOf_Switch Extra__Flag9              = ILIT(84)
--}
+lookUp          :: FAST_STRING -> Bool
+lookup_int              :: String -> Maybe Int
+lookup_def_int   :: String -> Int -> Int
+lookup_def_float :: String -> Float -> Float
+lookup_str       :: String -> Maybe String
 
-#ifndef DPH
-tagOf_Switch _ = case (panic "tagOf_Switch") of -- BUG avoidance
-                  s -> tagOf_Switch s
+unpacked_static_opts = unsafePerformIO (readIORef v_Static_hsc_opts)
+packed_static_opts   = map _PK_ unpacked_static_opts
 
-lAST_SWITCH_TAG = IBOX(tagOf_Switch D_simplifier_stats)
+lookUp     sw = sw `elem` packed_static_opts
+       
+lookup_str sw = firstJust (map (startsWith sw) unpacked_static_opts)
 
-#else {- Data Parallel Haskell -}
+lookup_int sw = case (lookup_str sw) of
+                 Nothing -> Nothing
+                 Just xx -> Just (read xx)
 
-tagOf_Switch PodizeIntelligent         = ILIT(90)
-tagOf_Switch PodizeAggresive           = ILIT(91)
-tagOf_Switch PodizeVeryAggresive       = ILIT(92)
-tagOf_Switch PodizeExtremelyAggresive  = ILIT(93)
-tagOf_Switch D_dump_pod                        = ILIT(94)
-tagOf_Switch D_dump_psimpl             = ILIT(95)
-tagOf_Switch D_dump_nextC              = ILIT(96)
+lookup_def_int sw def = case (lookup_str sw) of
+                           Nothing -> def              -- Use default
+                           Just xx -> read xx
 
-tagOf_Switch _ = case (panic "tagOf_Switch") of -- BUG avoidance
-                  s -> tagOf_Switch s
+lookup_def_float sw def = case (lookup_str sw) of
+                           Nothing -> def              -- Use default
+                           Just xx -> read xx
 
-lAST_SWITCH_TAG = IBOX(tagOf_Switch D_dump_nextC)
 
-#endif {- Data Parallel Haskell -}
+{-
+ Putting the compiler options into temporary at-files
+ may turn out to be necessary later on if we turn hsc into
+ a pure Win32 application where I think there's a command-line
+ length limit of 255. unpacked_opts understands the @ option.
+
+unpacked_opts :: [String]
+unpacked_opts =
+  concat $
+  map (expandAts) $
+  map _UNPK_ argv  -- NOT ARGV any more: v_Static_hsc_opts
+  where
+   expandAts ('@':fname) = words (unsafePerformIO (readFile fname))
+   expandAts l = [l]
+-}
 \end{code}
 
-(Note For Will): Could you please leave a little extra room between
-your last option and @D_dump_spec@... Thanks... jon...
+%************************************************************************
+%*                                                                     *
+\subsection{Static options}
+%*                                                                     *
+%************************************************************************
 
 \begin{code}
-tagOf_SimplSwitch SimplOkToDupCode             =(ILIT(0) :: FAST_INT)
-tagOf_SimplSwitch SimplFloatLetsExposingWHNF   = ILIT(1)
-tagOf_SimplSwitch SimplOkToFloatPrimOps                = ILIT(2)
-tagOf_SimplSwitch SimplAlwaysFloatLetsFromLets = ILIT(3)
-tagOf_SimplSwitch SimplDoCaseElim              = ILIT(4)
-tagOf_SimplSwitch SimplReuseCon                        = ILIT(5)
-tagOf_SimplSwitch SimplCaseOfCase              = ILIT(6)
-tagOf_SimplSwitch SimplLetToCase               = ILIT(7)
---UNUSED:tagOf_SimplSwitch SimplOkToInlineInLambdas    = ILIT(8)
-tagOf_SimplSwitch SimplMayDeleteConjurableIds  = ILIT(9)
-tagOf_SimplSwitch SimplPedanticBottoms         = ILIT(10)
-tagOf_SimplSwitch SimplDoArityExpand           = ILIT(11)
-tagOf_SimplSwitch SimplDoFoldrBuild            = ILIT(12)
-tagOf_SimplSwitch SimplDoNewOccurAnal          = ILIT(13)
-tagOf_SimplSwitch SimplDoInlineFoldrBuild      = ILIT(14)
-tagOf_SimplSwitch IgnoreINLINEPragma           = ILIT(15)
-tagOf_SimplSwitch SimplDoLambdaEtaExpansion    = ILIT(16)
---UNUSED:tagOf_SimplSwitch SimplDoMonadEtaExpansion    = ILIT(17)
-tagOf_SimplSwitch SimplDoEtaReduction          = ILIT(18)
-tagOf_SimplSwitch EssentialUnfoldingsOnly      = ILIT(19)
-tagOf_SimplSwitch ShowSimplifierProgress       = ILIT(20)
-tagOf_SimplSwitch (MaxSimplifierIterations _)  = ILIT(21)
-tagOf_SimplSwitch (SimplUnfoldingUseThreshold _)      = ILIT(22)
-tagOf_SimplSwitch (SimplUnfoldingCreationThreshold _) = ILIT(23)
-tagOf_SimplSwitch KeepSpecPragmaIds            = ILIT(24)
-tagOf_SimplSwitch KeepUnusedBindings           = ILIT(25)
-tagOf_SimplSwitch SimplNoLetFromCase           = ILIT(26)
-tagOf_SimplSwitch SimplNoLetFromApp            = ILIT(27)
-tagOf_SimplSwitch SimplNoLetFromStrictLet      = ILIT(28)
--- If you add anything here, be sure to change lAST_SIMPL_SWITCH_TAG, too!
+-- debugging opts
+opt_PprStyle_NoPrags           = lookUp  SLIT("-dppr-noprags")
+opt_PprStyle_Debug             = lookUp  SLIT("-dppr-debug")
+opt_PprStyle_RawTypes          = lookUp  SLIT("-dppr-rawtypes")
+opt_PprUserLength              = lookup_def_int "-dppr-user-length" 5 --ToDo: give this a name
+
+-- profiling opts
+opt_AutoSccsOnAllToplevs       = lookUp  SLIT("-fauto-sccs-on-all-toplevs")
+opt_AutoSccsOnExportedToplevs  = lookUp  SLIT("-fauto-sccs-on-exported-toplevs")
+opt_AutoSccsOnIndividualCafs   = lookUp  SLIT("-fauto-sccs-on-individual-cafs")
+opt_AutoSccsOnDicts            = lookUp  SLIT("-fauto-sccs-on-dicts")
+opt_SccProfilingOn             = lookUp  SLIT("-fscc-profiling")
+opt_DoTickyProfiling           = lookUp  SLIT("-fticky-ticky")
+
+-- language opts
+opt_AllStrict                  = lookUp  SLIT("-fall-strict")
+opt_NoMonomorphismRestriction  = lookUp  SLIT("-fno-monomorphism-restriction")
+opt_DictsStrict                        = lookUp  SLIT("-fdicts-strict")
+opt_IrrefutableTuples          = lookUp  SLIT("-firrefutable-tuples")
+opt_MaxContextReductionDepth   = lookup_def_int "-fcontext-stack" mAX_CONTEXT_REDUCTION_DEPTH
+opt_NumbersStrict              = lookUp  SLIT("-fnumbers-strict")
+opt_Parallel                   = lookUp  SLIT("-fparallel")
+opt_SMP                                = lookUp  SLIT("-fsmp")
+
+-- optimisation opts
+opt_NoMethodSharing            = lookUp  SLIT("-fno-method-sharing")
+opt_DoSemiTagging              = lookUp  SLIT("-fsemi-tagging")
+opt_FoldrBuildOn               = lookUp  SLIT("-ffoldr-build-on")
+opt_LiberateCaseThreshold      = lookup_def_int "-fliberate-case-threshold" (10::Int)
+opt_StgDoLetNoEscapes          = lookUp  SLIT("-flet-no-escape")
+opt_UnfoldCasms                        = lookUp  SLIT("-funfold-casms-in-hi-file")
+opt_UsageSPOn                  = lookUp  SLIT("-fusagesp-on")
+opt_UnboxStrictFields          = lookUp  SLIT("-funbox-strict-fields")
 
 {-
-tagOf_SimplSwitch Extra__SimplFlag1            = ILIT(26)
-tagOf_SimplSwitch Extra__SimplFlag2            = ILIT(27)
-tagOf_SimplSwitch Extra__SimplFlag3            = ILIT(28)
-tagOf_SimplSwitch Extra__SimplFlag4            = ILIT(29)
-tagOf_SimplSwitch Extra__SimplFlag5            = ILIT(30)
-tagOf_SimplSwitch Extra__SimplFlag6            = ILIT(31)
-tagOf_SimplSwitch Extra__SimplFlag8            = ILIT(32)
+   The optional '-inpackage=P' flag tells what package
+   we are compiling this module for.
+   The Prelude, for example is compiled with '-inpackage std'
 -}
-
-tagOf_SimplSwitch _ = case (panic "tagOf_SimplSwitch") of -- BUG avoidance
-                       s -> tagOf_SimplSwitch s
-
-lAST_SIMPL_SWITCH_TAG = IBOX(tagOf_SimplSwitch SimplNoLetFromStrictLet)
+opt_InPackage                  = case lookup_str "-inpackage=" of
+                                   Just p  -> _PK_ p
+                                   Nothing -> SLIT("Main")     -- The package name if none is specified
+
+opt_EmitCExternDecls           = lookUp  SLIT("-femit-extern-decls")
+opt_EnsureSplittableC          = lookUp  SLIT("-fglobalise-toplev-names")
+opt_GranMacros                 = lookUp  SLIT("-fgransim")
+opt_HiVersion                  = read cProjectVersionInt :: Int
+opt_HistorySize                        = lookup_def_int "-fhistory-size" 20
+opt_IgnoreAsserts               = lookUp  SLIT("-fignore-asserts")
+opt_IgnoreIfacePragmas         = lookUp  SLIT("-fignore-interface-pragmas")
+opt_NoHiCheck                   = lookUp  SLIT("-fno-hi-version-check")
+opt_OmitBlackHoling            = lookUp  SLIT("-dno-black-holing")
+opt_OmitInterfacePragmas       = lookUp  SLIT("-fomit-interface-pragmas")
+opt_RuntimeTypes               = lookUp  SLIT("-fruntime-types")
+
+-- Simplifier switches
+opt_SimplNoPreInlining         = lookUp  SLIT("-fno-pre-inlining")
+       -- NoPreInlining is there just to see how bad things
+       -- get if you don't do it!
+opt_SimplDoEtaReduction                = lookUp  SLIT("-fdo-eta-reduction")
+opt_SimplDoLambdaEtaExpansion  = lookUp  SLIT("-fdo-lambda-eta-expansion")
+opt_SimplCaseMerge             = lookUp  SLIT("-fcase-merge")
+opt_SimplExcessPrecision       = lookUp  SLIT("-fexcess-precision")
+
+-- Unfolding control
+opt_UF_CreationThreshold       = lookup_def_int "-funfolding-creation-threshold"  (45::Int)
+opt_UF_UseThreshold            = lookup_def_int "-funfolding-use-threshold"       (8::Int)     -- Discounts can be big
+opt_UF_FunAppDiscount          = lookup_def_int "-funfolding-fun-discount"        (6::Int)     -- It's great to inline a fn
+opt_UF_KeenessFactor           = lookup_def_float "-funfolding-keeness-factor"    (1.5::Float)
+opt_UF_UpdateInPlace           = lookUp  SLIT("-funfolding-update-in-place")
+
+opt_UF_CheapOp  = ( 1 :: Int)  -- Only one instruction; and the args are charged for
+opt_UF_DearOp   = ( 4 :: Int)
+                       
+opt_NoPruneDecls               = lookUp  SLIT("-fno-prune-decls")
+opt_NoPruneTyDecls             = lookUp  SLIT("-fno-prune-tydecls")
+opt_Static                     = lookUp  SLIT("-static")
+opt_Unregisterised             = lookUp  SLIT("-funregisterised")
+opt_EmitExternalCore           = lookUp  SLIT("-fext-core")
 \end{code}
 
 %************************************************************************
 %*                                                                     *
-\subsection[CmdLineOpts-lookup]{Switch lookup}
+\subsection{List of static hsc flags}
 %*                                                                     *
 %************************************************************************
 
 \begin{code}
-isAmong             :: [GlobalSwitch]     -> GlobalSwitch     -> SwitchResult
-isAmongSimpl :: [SimplifierSwitch] -> SimplifierSwitch -> SwitchResult
-
-isAmong on_switches
-  = let
-       tidied_on_switches = foldl rm_dups [] on_switches
-
-       sw_tbl :: Array Int SwitchResult
+isStaticHscFlag f =
+  f `elem` [
+       "fauto-sccs-on-all-toplevs",
+       "fauto-sccs-on-exported-toplevs",
+       "fauto-sccs-on-individual-cafs",
+       "fauto-sccs-on-dicts",
+       "fscc-profiling",
+       "fticky-ticky",
+       "fall-strict",
+       "fdicts-strict",
+       "firrefutable-tuples",
+       "fnumbers-strict",
+       "fparallel",
+       "fsmp",
+       "fsemi-tagging",
+       "ffoldr-build-on",
+       "flet-no-escape",
+       "funfold-casms-in-hi-file",
+       "fusagesp-on",
+       "funbox-strict-fields",
+       "femit-extern-decls",
+       "fglobalise-toplev-names",
+       "fgransim",
+       "fignore-asserts",
+       "fignore-interface-pragmas",
+       "fno-hi-version-check",
+       "dno-black-holing",
+       "fno-method-sharing",
+        "fno-monomorphism-restriction",
+       "fomit-interface-pragmas",
+       "fruntime-types",
+       "fno-pre-inlining",
+       "fdo-eta-reduction",
+       "fdo-lambda-eta-expansion",
+       "fcase-merge",
+       "fexcess-precision",
+       "funfolding-update-in-place",
+       "fno-prune-decls",
+       "fno-prune-tydecls",
+       "static",
+       "funregisterised",
+       "fext-core"
+       ]
+  || any (flip prefixMatch f) [
+       "fcontext-stack",
+       "fliberate-case-threshold",
+       "fhistory-size",
+       "funfolding-creation-threshold",
+       "funfolding-use-threshold",
+       "funfolding-fun-discount",
+       "funfolding-keeness-factor"
+     ]
+\end{code}
 
-       sw_tbl = (array (0, lAST_SWITCH_TAG) -- bounds...
-                       all_undefined)
-                // defined_elems
+%************************************************************************
+%*                                                                     *
+\subsection{Switch ordering}
+%*                                                                     *
+%************************************************************************
 
-       all_undefined = [ i := SwBool False | i <- [0 .. lAST_SWITCH_TAG ] ]
+These things behave just like enumeration types.
 
-       defined_elems = map mk_assoc_elem tidied_on_switches
-    in
-#ifndef __GLASGOW_HASKELL__
-    \ switch -> sw_tbl ! IBOX((tagOf_Switch switch))   -- but this is fast!
-#else
-    -- and this is faster!
-    -- (avoid some unboxing, bounds checking, and other horrible things:)
-    case sw_tbl of { _Array bounds_who_needs_'em stuff ->
-    \ switch ->
-       case (indexArray# stuff (tagOf_Switch switch)) of
-         _Lift v -> v
-    }
-#endif
-  where
-    mk_assoc_elem k@(ProduceC  str) = IBOX(tagOf_Switch k) := SwString str
-    mk_assoc_elem k@(ProduceS  str) = IBOX(tagOf_Switch k) := SwString str
-    mk_assoc_elem k@(ProduceHi str) = IBOX(tagOf_Switch k) := SwString str
---UNUSED:    mk_assoc_elem k@(ProduceHu str) = IBOX(tagOf_Switch k) := SwString str
-    mk_assoc_elem k@(SccGroup  str) = IBOX(tagOf_Switch k) := SwString str
-    mk_assoc_elem k@(AsmTarget str) = IBOX(tagOf_Switch k) := SwString str
-    mk_assoc_elem k@(EnsureSplittableC str) = IBOX(tagOf_Switch k) := SwString str
+\begin{code}
+instance Eq SimplifierSwitch where
+    a == b = tagOf_SimplSwitch a ==# tagOf_SimplSwitch b
 
-    mk_assoc_elem k@(UnfoldingUseThreshold      lvl) = IBOX(tagOf_Switch k) := SwInt lvl
-    mk_assoc_elem k@(UnfoldingCreationThreshold lvl) = IBOX(tagOf_Switch k) := SwInt lvl
-    mk_assoc_elem k@(UnfoldingOverrideThreshold lvl) = IBOX(tagOf_Switch k) := SwInt lvl
+instance Ord SimplifierSwitch where
+    a <  b  = tagOf_SimplSwitch a <# tagOf_SimplSwitch b
+    a <= b  = tagOf_SimplSwitch a <=# tagOf_SimplSwitch b
 
-    mk_assoc_elem k@(ReturnInRegsThreshold lvl) = IBOX(tagOf_Switch k) := SwInt lvl
 
-    mk_assoc_elem k = IBOX(tagOf_Switch k) := SwBool True -- I'm here, Mom!
+tagOf_SimplSwitch (SimplInlinePhase _)         = _ILIT(1)
+tagOf_SimplSwitch (MaxSimplifierIterations _)  = _ILIT(2)
+tagOf_SimplSwitch DontApplyRules               = _ILIT(3)
+tagOf_SimplSwitch SimplLetToCase               = _ILIT(4)
+tagOf_SimplSwitch NoCaseOfCase                 = _ILIT(5)
 
-    -- cannot have duplicates if we are going to use the array thing
+-- If you add anything here, be sure to change lAST_SIMPL_SWITCH_TAG, too!
 
-    rm_dups switches_so_far switch
-      = if switch `is_elem` switches_so_far
-       then switches_so_far
-       else switch : switches_so_far
-      where
-       sw `is_elem` []     = False
-       sw `is_elem` (s:ss) = (tagOf_Switch sw) _EQ_ (tagOf_Switch s)
-                           || sw `is_elem` ss
+lAST_SIMPL_SWITCH_TAG = 5
 \end{code}
 
-Same thing for @SimplifierSwitches@; for efficiency reasons, we
-probably do {\em not} want something overloaded.
- \begin{code}
-isAmongSimpl on_switches
+%************************************************************************
+%*                                                                     *
+\subsection{Switch lookup}
+%*                                                                     *
+%************************************************************************
+
+\begin{code}
+isAmongSimpl :: [SimplifierSwitch] -> SimplifierSwitch -> SwitchResult
+isAmongSimpl on_switches               -- Switches mentioned later occur *earlier*
+                                       -- in the list; defaults right at the end.
   = let
        tidied_on_switches = foldl rm_dups [] on_switches
+               -- The fold*l* ensures that we keep the latest switches;
+               -- ie the ones that occur earliest in the list.
 
        sw_tbl :: Array Int SwitchResult
-
        sw_tbl = (array (0, lAST_SIMPL_SWITCH_TAG) -- bounds...
                        all_undefined)
                 // defined_elems
 
-       all_undefined = [ i := SwBool False | i <- [0 .. lAST_SIMPL_SWITCH_TAG ] ]
+       all_undefined = [ (i, SwBool False) | i <- [0 .. lAST_SIMPL_SWITCH_TAG ] ]
 
        defined_elems = map mk_assoc_elem tidied_on_switches
     in
-#ifndef __GLASGOW_HASKELL__
-    \ switch -> sw_tbl ! IBOX((tagOf_SimplSwitch switch)) -- but this is fast!
-#else
-    -- and this is faster!
     -- (avoid some unboxing, bounds checking, and other horrible things:)
-    case sw_tbl of { _Array bounds_who_needs_'em stuff ->
+#if __GLASGOW_HASKELL__ < 405
+    case sw_tbl of { Array bounds_who_needs_'em stuff ->
+#else
+    case sw_tbl of { Array _ _ stuff ->
+#endif
     \ switch ->
        case (indexArray# stuff (tagOf_SimplSwitch switch)) of
-         _Lift v -> v
-    }
+#if __GLASGOW_HASKELL__ < 400
+         Lift v -> v
+#elif __GLASGOW_HASKELL__ < 403
+         (# _, v #) -> v
+#else
+         (# v #) -> v
 #endif
+    }
   where
-    mk_assoc_elem k@(MaxSimplifierIterations lvl) = IBOX(tagOf_SimplSwitch k) := SwInt lvl
-    mk_assoc_elem k@(SimplUnfoldingUseThreshold      i) = IBOX(tagOf_SimplSwitch k) := SwInt i
-    mk_assoc_elem k@(SimplUnfoldingCreationThreshold i) = IBOX(tagOf_SimplSwitch k) := SwInt i
-
-    mk_assoc_elem k = IBOX(tagOf_SimplSwitch k) := SwBool   True -- I'm here, Mom!
+    mk_assoc_elem k@(MaxSimplifierIterations lvl)
+       = (iBox (tagOf_SimplSwitch k), SwInt lvl)
+    mk_assoc_elem k@(SimplInlinePhase n)
+       = (iBox (tagOf_SimplSwitch k), SwInt n)
+    mk_assoc_elem k
+       = (iBox (tagOf_SimplSwitch k), SwBool True) -- I'm here, Mom!
 
     -- cannot have duplicates if we are going to use the array thing
-
     rm_dups switches_so_far switch
       = if switch `is_elem` switches_so_far
        then switches_so_far
        else switch : switches_so_far
       where
        sw `is_elem` []     = False
-       sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) _EQ_ (tagOf_SimplSwitch s)
+       sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) ==# (tagOf_SimplSwitch s)
                            || sw `is_elem` ss
 \end{code}
 
+
 %************************************************************************
 %*                                                                     *
-\subsection[CmdLineOpts-misc]{Misc functions for command-line options}
+\subsection{Misc functions for command-line options}
 %*                                                                     *
 %************************************************************************
 
@@ -976,22 +763,28 @@ switchIsOn lookup_fn switch
       SwBool False -> False
       _                   -> True
 
-stringSwitchSet :: (switch -> SwitchResult)
-               -> (String -> switch)
-               -> Maybe String
-
-stringSwitchSet lookup_fn switch
-  = case (lookup_fn (switch (panic "stringSwitchSet"))) of
-      SwString str -> Just str
-      _                   -> Nothing
-
 intSwitchSet :: (switch -> SwitchResult)
             -> (Int -> switch)
             -> Maybe Int
 
 intSwitchSet lookup_fn switch
-  = -- pprTrace "intSwitchSet:" (ppInt (IBOX (tagOf_Switch (switch (panic "xxx"))))) $
-    case (lookup_fn (switch (panic "intSwitchSet"))) of
+  = case (lookup_fn (switch (panic "intSwitchSet"))) of
       SwInt int -> Just int
       _                -> Nothing
 \end{code}
+
+\begin{code}
+startsWith :: String -> String -> Maybe String
+-- startsWith pfx (pfx++rest) = Just rest
+
+startsWith []     str = Just str
+startsWith (c:cs) (s:ss)
+  = if c /= s then Nothing else startsWith cs ss
+startsWith  _    []  = Nothing
+
+endsWith  :: String -> String -> Maybe String
+endsWith cs ss
+  = case (startsWith (reverse cs) (reverse ss)) of
+      Nothing -> Nothing
+      Just rs -> Just (reverse rs)
+\end{code}